From a7684982503ace53def47f96c53f71e0ddacfbb8 Mon Sep 17 00:00:00 2001
From: Jon Chambers <jon@signal.org>
Date: Wed, 21 Jun 2023 12:26:35 -0400
Subject: [PATCH] Record general message delivery latency

---
 .../controllers/MessageController.java        | 19 +++++--------------
 .../textsecuregcm/metrics/MessageMetrics.java | 12 ++++++++++++
 .../websocket/WebSocketConnection.java        |  2 ++
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/controllers/MessageController.java b/service/src/main/java/org/whispersystems/textsecuregcm/controllers/MessageController.java
index 3a4362a94..f73c1a446 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/controllers/MessageController.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/controllers/MessageController.java
@@ -100,8 +100,6 @@ import org.whispersystems.textsecuregcm.storage.ReportMessageManager;
 import org.whispersystems.textsecuregcm.util.DestinationDeviceValidator;
 import org.whispersystems.textsecuregcm.util.Pair;
 import org.whispersystems.textsecuregcm.util.Util;
-import org.whispersystems.textsecuregcm.util.ua.UnrecognizedUserAgentException;
-import org.whispersystems.textsecuregcm.util.ua.UserAgentUtil;
 import org.whispersystems.textsecuregcm.websocket.WebSocketConnection;
 import org.whispersystems.websocket.Stories;
 import reactor.core.scheduler.Scheduler;
@@ -536,21 +534,14 @@ public class MessageController {
 
           final OutgoingMessageEntityList messages = new OutgoingMessageEntityList(envelopes
               .map(OutgoingMessageEntity::fromEnvelope)
-              .peek(
-                  outgoingMessageEntity -> MessageMetrics.measureAccountOutgoingMessageUuidMismatches(auth.getAccount(),
-                      outgoingMessageEntity))
+              .peek(outgoingMessageEntity -> {
+                MessageMetrics.measureAccountOutgoingMessageUuidMismatches(auth.getAccount(), outgoingMessageEntity);
+                MessageMetrics.measureOutgoingMessageLatency(outgoingMessageEntity.serverTimestamp(), "rest", userAgent);
+              })
               .collect(Collectors.toList()),
               messagesAndHasMore.second());
 
-          String platform;
-
-          try {
-            platform = UserAgentUtil.parseUserAgentString(userAgent).getPlatform().name().toLowerCase();
-          } catch (final UnrecognizedUserAgentException ignored) {
-            platform = "unrecognized";
-          }
-
-          Metrics.summary(OUTGOING_MESSAGE_LIST_SIZE_BYTES_DISTRIBUTION_NAME, "platform", platform)
+          Metrics.summary(OUTGOING_MESSAGE_LIST_SIZE_BYTES_DISTRIBUTION_NAME, Tags.of(UserAgentTagUtil.getPlatformTag(userAgent)))
               .record(estimateMessageListSizeBytes(messages));
 
           return messages;
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/metrics/MessageMetrics.java b/service/src/main/java/org/whispersystems/textsecuregcm/metrics/MessageMetrics.java
index 87cc92d7d..38695b92d 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/metrics/MessageMetrics.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/metrics/MessageMetrics.java
@@ -8,7 +8,11 @@ package org.whispersystems.textsecuregcm.metrics;
 import static org.whispersystems.textsecuregcm.metrics.MetricsUtil.name;
 
 import io.micrometer.core.instrument.Metrics;
+import java.time.Duration;
+import java.time.Instant;
 import java.util.UUID;
+import io.micrometer.core.instrument.Tag;
+import io.micrometer.core.instrument.Tags;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.whispersystems.textsecuregcm.entities.MessageProtos;
@@ -22,6 +26,8 @@ public final class MessageMetrics {
   private static final String MISMATCHED_ACCOUNT_ENVELOPE_UUID_COUNTER_NAME = name(MessageMetrics.class,
       "mismatchedAccountEnvelopeUuid");
 
+  private static final String DELIVERY_LATENCY_TIMER_NAME = name(MessageMetrics.class, "deliveryLatency");
+
   public static void measureAccountOutgoingMessageUuidMismatches(final Account account,
       final OutgoingMessageEntity outgoingMessage) {
     measureAccountDestinationUuidMismatches(account, outgoingMessage.destinationUuid());
@@ -48,4 +54,10 @@ public final class MessageMetrics {
     }
   }
 
+  public static void measureOutgoingMessageLatency(final long serverTimestamp, final String channel, final String userAgent) {
+    Metrics.timer(DELIVERY_LATENCY_TIMER_NAME, Tags.of(
+            UserAgentTagUtil.getPlatformTag(userAgent),
+            Tag.of("channel", channel)))
+        .record(Duration.between(Instant.ofEpochMilli(serverTimestamp), Instant.now()));
+  }
 }
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/websocket/WebSocketConnection.java b/service/src/main/java/org/whispersystems/textsecuregcm/websocket/WebSocketConnection.java
index 575b3e420..e5a677709 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/websocket/WebSocketConnection.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/websocket/WebSocketConnection.java
@@ -207,6 +207,8 @@ public class WebSocketConnection implements MessageAvailabilityListener, Displac
         .whenComplete((ignored, throwable) -> {
           if (throwable != null) {
             sendFailuresMeter.mark();
+          } else {
+            MessageMetrics.measureOutgoingMessageLatency(message.getServerTimestamp(), "websocket", client.getUserAgent());
           }
         }).thenCompose(response -> {
           final CompletableFuture<Void> result;